Update Gemfile dependencies.

Gemfile.lock

@@ -1,6 +1,6 @@
 GIT
   remote: git://github.com/rails/rails.git
-  revision: d41154094a332a3dd797c4148894fbcd1e5ad5ff
+  revision: e918516d2fdfa24e5fc04ef14e371f08f4a8315f
   specs:
     actionpack (4.2.0.alpha)
       actionview (= 4.2.0.alpha)
@@ -36,23 +36,19 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    atomic (1.1.15)
     builder (3.2.2)
     country_select (1.1.3)
     erubis (2.7.0)
     ffi2-generators (0.1.1)
     i18n (0.6.9)
     json (1.8.1)
-    minitest (5.3.0)
+    minitest (5.3.3)
     rack (1.5.2)
     rack-test (0.6.2)
       rack (>= 1.0)
-    rake (10.1.1)
-    rubinius-compiler (2.1.0)
+    rake (10.3.1)
     rubinius-coverage (2.0.3)
-    rubinius-debugger (2.0.2)
-      rubinius-compiler (~> 2.0)
-      rubysl-readline (~> 2.0)
+    rubinius-debugger (2.0.3)
     rubinius-developer_tools (2.0.0)
       rubinius-coverage (~> 2.0)
       rubinius-debugger (~> 2.0)
@@ -221,7 +217,7 @@ GEM
       rubysl-shellwords (~> 2.0)
     rubysl-ostruct (2.0.4)
     rubysl-pathname (2.0.0)
-    rubysl-prettyprint (2.0.2)
+    rubysl-prettyprint (2.0.3)
     rubysl-prime (2.0.1)
     rubysl-profile (2.0.0)
     rubysl-profiler (2.0.1)
@@ -249,7 +245,7 @@ GEM
     rubysl-thwait (2.0.0)
     rubysl-time (2.0.3)
     rubysl-timeout (2.0.0)
-    rubysl-tmpdir (2.0.0)
+    rubysl-tmpdir (2.0.1)
     rubysl-tsort (2.0.1)
     rubysl-un (2.0.0)
       rubysl-fileutils (~> 2.0)
@@ -260,9 +256,8 @@ GEM
     rubysl-xmlrpc (2.0.0)
     rubysl-yaml (2.0.4)
     rubysl-zlib (2.0.1)
-    thor (0.18.1)
-    thread_safe (0.2.0)
-      atomic (>= 1.1.7, < 2)
+    thor (0.19.1)
+    thread_safe (0.3.3)
     tzinfo (1.1.0)
       thread_safe (~> 0.1)